Exam Hack | CIE A2 Maths | S2 | Poisson Distribution Question
Added 2022-09-20 02:56:33 +0000 UTCExam Hack - S1 - Binomial Distribution: https://youtu.be/dx2AHaUvt4U
Exam Hack - S1 - Normal Distribution - 2: https://youtu.be/mX8IU4hofvg
Proof that Binomial tends to Poisson: https://youtu.be/ceOwlHnVCqo
Normal Approximation to the Poisson: https://youtu.be/CCqWkJ_pqNU
Comments
hey, Jacob, in the 23rd [a] question, you made a mistake, the answer is 0.144
Lyndon Dias
2023-12-20 08:25:44 +0000 UTCHi, don't know why in Q15 s2019_61, they used 115 as mean and standard deviation, also if i were to use 2.3, i get the z value as 71.3, which i don't think i can find on the z distribution graph. so what would i do in that case. Please try and help soon, I have my exam on Monday lol
Samhitha Ahoratra
2023-10-14 15:12:48 +0000 UTChey, around 31:28, wasn't z already less than -0.982, so when subtracting you switched the sign, and then switched it again. I don't understand why you switched the sign the first time.
Samhitha Ahoratra
2023-10-14 13:56:15 +0000 UTCMaybe you should recap the S1 Normal distribution content on my Youtube. This is just to do with the symmetry of the distribution. Also watch the videos I link in the description box bellow the video.
Intuitive
2023-02-26 11:30:06 +0000 UTCOh you're talking about continuity correction. You're plussing 0.5 for that case because > 40 needs to exclude 40 to be as accurate as possible, so you use > 40.5 not > 39.5, as 39.5 would include 40. Basically, if you're confused about this look up continuity corrections for the normal distribution approximation. I talk about it as well in my "S1 Normal Distribution - part 2" on YouTube.
Intuitive
2023-02-26 11:28:05 +0000 UTCin question 4), it switches from poisson distribution to normal distribution, so in this questions the normal distribution is X~N(31, 31) since X~Po(31), and they are asking me to work out P(X>40), typically when I've seen '>' signs, I usually -0.5 from the X value (40 in this case) to plug into the equation- so i got (39.5 - 31)/square root 31, however when I checked the ms, they used 40.5 (+0.5) instead of 39.5 (-0.5) which is the value I was typically told to use and had worked for me in past questions. So now I'm unsure as to when I should be minus-ing or plus-ing the 0.5 error.
Eirene Chiam
2023-02-26 10:57:22 +0000 UTCWhen would you get a mean of +/-? I can't see how that would be possible. I guess if you did you'd plug in the '+' value and the '-' value getting two different solutions when plugging it into your Poisson Density function.
Intuitive
2023-02-22 07:42:34 +0000 UTCAlso, having some problems with poison to normal distributionq2ii) in the worksheet as i got a negative z value and I calculated the 1- -ve z value to get the probability but when I checked the answer at the back it’s just the +ve version of the z value?
Eirene Chiam
2023-02-22 07:24:25 +0000 UTCHi, thanks for all the great content 😊, quick question, when it switches from poison to normal and we have to +/- 0.5 to the µ, how do we know when to -0.5 and when to +0.5?
Eirene Chiam
2023-02-22 07:14:16 +0000 UTCHey, it’s nothing wrong, just a common slang here. If offended sorry. I love ur content.😄
Isfar Ahamed
2023-01-28 03:44:54 +0000 UTCTamil? I’ve spent time in Chennai, and this doesn’t sound like you’re saying something nice…
Intuitive
2023-01-26 19:28:31 +0000 UTCthala, LOL
Hamsavardan
2023-01-26 16:54:39 +0000 UTCpoda lossu
Isfar Ahamed
2023-01-23 06:19:51 +0000 UTCMy guy
Intuitive
2022-11-20 02:56:35 +0000 UTCreally well kept beard 10/10
accountfor intuitive
2022-11-19 10:00:46 +0000 UTCPlease can you do a Hypothesis testing video.
Ryan
2022-10-19 17:47:47 +0000 UTCVery well explained, thank you!
Maria Aparicio
2022-10-08 17:15:20 +0000 UTCI’m working on next one now it’ll be out in next couple days
Intuitive
2022-09-22 08:38:10 +0000 UTCWhen can we get the other s2 topics
Tapiwa
2022-09-22 06:42:33 +0000 UTC
